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چکیده
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N-heterocyclic carbenes (NHCs) represent a growing class of ligands because of several typical features such as stability to air and moisture, low toxicity, and strong σ-donor and poor π-acceptor properties [1,2]. Also these ligands are efficient catalysts in important chemical transformation such as allylic arylation, Ni and Pd carbon-carbon coupling reactions and Rh catalysts hydrosilylations [3,4]. In this context, we designed several novel chiral C1-symmetric NHCs and synthesis them in high yield and enantiomeric excess from chiral diamine that prepared from inexpensive and available chiral pool amino acids. Then the chiral organometallic catalysts were prepared by the reaction of these NHCs ligands with transition metals in order to investigate them in various asymmetry reactions such as Micheal addition and C-C coupling reactions. In continuation, we optimized the experimental conditions for these reactions by testing changeable parameters such as temperature, catalyst loading, solvents and additives to prepare enantiomerically pure or enriched desirable product.
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